Buds that contain or produce only leaves are =leaf-buds=. Those which contain only flowers are =flower-buds= or =fruit-buds=. The latter occur on peach, almond, apricot, and many very early spring-flowering plants. The single flower is emerging from the apricot bud in Fig. 147. A longitudinal section of this bud, enlarged, is shown in Fig. 148. Those that contain both leaves and flowers are =mixed buds=, as in pear, apple, and most late spring-flowering plants. _Fruit buds are usually thicker or stouter than leaf-buds. They are borne in different positions on different plants._ In some plants (apple, pear) they are on the ends of short branches or spurs; in others (peach, red maple) they are along the sides of the last year’s growths. In Fig. 149 are shown three fruit-buds and one leaf-bud on _E_, and leaf-buds on _A_. See also Figs. 150, 151, 152, 153, and explain. [Illustration: FIG. 150.—FRUIT-BUDS OF APPLE ON SPURS: a dormant bud at the top.] [Illustration: FIG. 151.—CLUSTER OF FRUIT-BUDS OF SWEET CHERRY, with one pointed leaf-bud in centre.] [Illustration: FIG. 152.—TWO FRUIT-BUDS OF PEACH with a leaf-bud between.] [Illustration: FIG. 153.—OPENING OF LEAF-BUDS AND FLOWER-BUDS OF APPLE.] “_The burst of spring_” means in large part the opening of the buds. _Everything was made ready the fall before. The embryo shoots and flowers were tucked away, and the food was stored._ The warm rain falls, and the shutters open and the sleepers wake. =Arrangement of Buds.=—We have found that leaves are usually arranged in a definite order; buds are borne in the axils of leaves: therefore _buds must exhibit phyllotaxy_. Moreover, branches grow from buds: branches, therefore, should show a definite arrangement. Usually, however, they do not show this arrangement because _not all the buds grow and not all the branches live_. (See Chaps. II and III.) It is apparent, however, that the mode of arrangement of buds determines to some extent the form of the tree. Compare bud arrangement in pine or fir with that in maple or apple. [Illustration: FIG. 154.—OAK SPRAY. How are the leaves borne with reference to the annual growths?] The uppermost buds on any twig, if they are well matured, are usually the larger and stronger and they are the most likely to grow the next spring; therefore, branches tend to be arranged in tiers (particularly well marked in spruces and firs). See Fig. 154 and explain it. =Winter Buds show what has been the Effect of Sunlight.=—Buds are borne in the axils of the leaves, and _the size or the vigour of the leaf determines to a large extent the size of the bud_. Notice that, in most instances, _the largest buds are nearest the tip_ (Fig. 157). If the largest buds are not near the tip, there is some special reason for it. Can you state it? Examine the shoots on trees and bushes. [Illustration: FIG. 155.—AN APPLE TWIG.] [Illustration: FIG. 156.—Same twig before leaves fell.]